London Olympics (Aug. 11, 2012)

Vera Santos of Portugal lays on the ground after finishing the women's 20-kilometer race walk competition at the 2012 Summer Olympics in London.

AP Photo/Mike Groll

Russia's Mariya Savinova, right, reacts as she crosses the finish line ahead of South Africa's Caster Semenya to win the women's 800-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London.

AP Photo/Anja Niedringhaus

John Joe Nevin of Ireland, in red, and Luke Campbell of Great Britain, in blue, fight during their men's bantamweight 56-kg gold medal boxing match at the 2012 Summer Olympics in London.

AP Photo/Ivan Sekretarev

Uzbekistan's Svetlana Radzivil reacts after clearing the bar in the women's high jump final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London.

AP Photo/Hassan Ammar

From left, United States' Justin Gatlin hands the baton to Tyson Gay, as Jamaica's Michael Frater hands the baton to Yohan Blake in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London.

(AP Photo/Hassan Ammar

Brazil's Fabiana Claudino (1) celebrates after the team defeated the USA 3-1 during a women's volleyball gold medal match at the 2012 Summer Olympics in London.

AP Photo/Chris O'Meara

Silver medalist Cao Zhongrong, of China, competes with horse Sweet Touch in the equestrian show jumping stage of the men's modern pentathlon, at the 2012 Summer Olympics in London.

AP Photo/Markus Schreiber

New Zealand's Stuart Farquhar takes a throw in the men's javelin throw final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London.

AP Photo/David J. Phillip

Yogeshwar Dutt of India celebrates after beating Ri Jong Myong of North Korea for the bronze medal during the men's 60-kg freestyle wrestling competition at the 2012 Summer Olympics in London.

AP Photo/Paul Sancya

United States' Brigetta Barrett reacts as she clears the bar in the women's high jump final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London.

AP Photo/Matt Dunham

Russia's Anna Chicherova celebrates after she cleared the bar to win gold in the women's high jump final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London.

AP Photo/Matt Dunham

Jamaica's Usain Bolt leads United States' Ryan Bailey to win the men's 4 x 100-meter relay final during the athletics in the Olympic Park during the 2012 Summer Olympic in London. Jamaica set a new world record with a time of 36.84 seconds.

AP Photo/Anja Niedringhaus

Hwang Woojin, of South Korea, and his horse Shearwater Oscar, fall down after the horse bucked after the starting bell sounded to start their run in the equestrian show jumping stage of the men's modern pentathlon at the 2012 Summer Olympics in London.

AP Photo/David Goldman

David Svoboda of Czech Republic poses with his gold medal after winning in the men's modern pentathlon at the 2012 Summer Olympics in London.

AP Photo/Markus Schreiber

The Netherlands' Tim Jenniskens and Germany's Thilo Stralkowski vie for the ball during the men's field hockey gold medal match at the 2012 Summer Olympics in London.

AP Photo/Eranga Jayawardena

Russia's Anna Chicherova reacts after she cleared the bar to win gold in the women's high jump final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London.

AP Photo/Matt Dunham

Jamaica's Usain Bolt celebrates his win in the men's 4 x 100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics in London. Jamaica set a new world record with a time of 36.84 seconds.

AP Photo/Anja Niedringhaus

Vera Santos of Portugal collapses after finishing in the 20-kilometers women's race walk competition, at the 2012 Summer Olympics in London.

AP Photo/Dmitry Lovetsky

Brazil's Jaqueline Carvalho (8) poses with her gold medal after defeating the USA at the 2012 Summer Olympics in London.